To that immortal ad slogan, "Does she ... or doesn't she?," the answer most likely is, "She does ... until she doesn't."

The stealthy behavior in question? Coloring your hair -- a process celebrated for letting women explore the presumed (and, alas, documented) benefits of keeping the gray at bay.

Being thought younger than your years may be helpful in the workplace, in your social circle -- or in your head.

News flash: When boomers began graying, hair coloring rates soared, accounting for at least half of salon revenues in the United States. Still, Mother Nature cannot forever be denied. One rule of thumb says that 50 percent of women's hair is 50 percent gray by age 50.

The issue then becomes how and when to scale back on the Light Chestnut Brown. Do you consult your spouse? What about friends irked by your gray, either seeing it as you throwing in the towel or, conversely, as smugly proclaiming that you're done with faking it -- that you're a natural woman. Should you start keeping a paper trail at work, just in case?

Camille Sypura, 42, began dyeing her hair about two years ago when she and her husband were trying to adopt a child. "I asked our case worker if I should color my hair and she said, 'If I were you, I would,'" said Sypura, who lives in Coon Rapids. So she did, until deciding last August that the upkeep was spendy, kind of a hassle and not fooling anybody.

"Coloring my hair doesn't make me look any younger; it just makes me look like I have my hair colored," she said. Not that Sypura surrendered to the actuarial tables. "I would rather spend my money on microdermabrasion or a Pilates class," she said. Actually, she's still spending money at the salon, taking her stylist's advice to use a rinse through the roots-growing-out phase. "But I'm looking forward to the end of this because I'm kind of proud of my gray."

Silver foxes unite

We're in the midst of a bout of "gray chic." Snow-capped Helen Mirren is acclaimed as sexy, while Kelly Osbourne, the 27-year-old reality TV personality, experimented with dyeing her hair gray last winter -- something she said she had wanted to do all her life. As usual, the pro-gray bandwagon tries a bit too hard, tossing around such terms as "gray panthers" and "glam-mas."

Make no mistake: Coloring your hair is normal. Sypura is among the almost seven in 10 women who color or have colored their hair, according to a Procter & Gamble survey. That's a huge leap from the 1950s, when fewer than one in 10 women tweaked nature. Then in 1956, Clairol's famous "Does she?" slogan debuted, leading over time to fewer and fewer states requiring hair color on driver's licenses.

The shift to ageless locks flowed from a confluence of science and culture, according to Anne Kreamer, a former Nickelodeon executive who in 2007 wrote "Going Gray: What I Learned About Beauty, Sex, Work, Motherhood, Authenticity, and Everything Else That Really Matters."

"In the 1960s, hair color became easy, affordable and safe, and women were going to work," Kreamer said during a phone interview. "They said, 'I can reinvent myself,' and those two things got linked and we never looked back."

Kreamer, 56, explored two subtly different assumptions that women have about going gray: that they no longer are attractive and that they look old. (And yes, this is a women's issue; most men don't care about hair as long it's still there.)

When Kreamer photoshopped pictures of herself with brown and gray hair, she found that people always guessed her age within a year, "telling me that the only people we fool into thinking we look younger is ourselves," she said, hair color being only one cue, along with wrinkles and skin tone. Then she set up two profiles on, identical but for hair color, and got more responses to her "silver" profile than her "brown."

Yet Kreamer grants that going gray isn't easy, and might not even be prudent. "We do live in an age-discrimination culture in terms of the business environment," she said. Few women executives show any gray, and a directory of U.S. congresswomen resembles a L'Oreal slide show. "We have no role models, women who are out front saying, 'You don't have to do this.'"

Appearance fuels attitude

Penelope Hilleman sees "going gray" from a different perspective. After seeing silver strands in her medium brown hair, she began coloring in her 30s, but decided in her early 40s to embrace reality, thinking that as long as it looked premature, it was cool.

"I came from a 'natural' mindset that didn't feel coloring should be necessary," said Hilleman, of Northfield. "And I chafed at the idea that women were expected to cover their gray or be perceived as old and frumpy, whereas men who were gray could be perceived more positively.

"But eventually I realized I felt old and frumpy. It start to weigh on me, which was not what I expected."

By the time she was 52, she'd grown used to people treating her as if she were 10 years older than she was, to men no longer making eye contact. Her confidence took a hit. She spoke up less often in meetings at the marketing firm where she works. Hilleman decided to cover the gray, taking the opportunity to improve on Mother Nature by choosing a warm auburn.

"The difference in how I feel now, and how I sense I am perceived, is striking," she said. "Now I feel energetic and decisive and freer to express opinions. I'm back."

Then she paused, as if pondering herself how hair color could make such a difference: "Isn't that strange?

Better grooming through science

Gray hair isn't really gray; it just lacks its original pigmentation and appears white because of how it reflects light. Genetics play a role, as Sypura knew.

"My mom was 37 when she had me, and I was 37 when I had my daughter," she said. "The first time I was called grandma was pretty horrendous. But Mom said, "Honey, you better just get used to it.'"

Yet Sypura and her mother were not prematurely gray. A study by the Journal of Investigative Dermatology found that most Caucasian people will begin to gray in their 20s and early 30s, Asian people in their late 30s, and African people not until their 40s.

The trouble is, having only a few gray hairs can make a lovely coiffure appear dull. So women begin coloring their hair, or find that a savvy stylist can help them weather the months while they aspire to Emmylou Harris status.

Science is on the case. Last fall, news leaked that L'Oreal is developing a pill based on a fruit extract that mimics an enzyme that helps cells produce pigment. In theory, the extract could keep hair from turning gray. Such a pill would have to be taken for life, however -- and ideally before the first gray hairs appear, "because we don't think it can reverse the process once it has started," one researcher told the Christian Science Monitor.

Mirror, mirror says it all

Mary Meehan, 57, tracks consumer trends through her Minneapolis firm, Panoramix Global. Her hair began turning white when she was 25. She's never colored it.

She says "granny chic" is getting attention "because there are more of us, and that makes it easier for others to consider it. The question is when and how do you make that choice."

Meehan sees several cultural forces coming to bear, among them the anti-bullying movement. If that seems unexpected, recall its message of being able to be who we are, regardless of physical traits. "Add on to that the green movement, which is about how the products we use are affecting our health," she said.

Finally, there's the specter of ageism. "Women are saying, We fought hard to get here. Boomers are maintaining their ground, whether that's real or perceived."

The ultimate judge stands before the bathroom mirror.

Sypura said one of her friends was irked by her decision to embrace her gray, but her husband has been wholly supportive. "He is a wise, wise man," she said, laughing. Mostly, she added, going gray has simplified her life by eliminating any sense of artifice.

"I'm not a good liar," she said. "I wish I was. I really do! But I find it freeing to just be what I really am."

Kim Ode • 612-673-7185